IMIBIO-SL   20937
INSTITUTO MULTIDISCIPLINARIO DE INVESTIGACIONES BIOLOGICAS DE SAN LUIS
Unidad Ejecutora - UE
congresos y reuniones científicas
Título:
Resveratrol rescues insulin sensitivity in obese adipocytes
Autor/es:
DARIO C. RAMIREZ; SANDRA E. GOMEZ-MEJIBA
Lugar:
CABA
Reunión:
Conferencia; VI INTERNATIONAL CONFERENCE ON POLYPHENOLS AND HEALTH; 2013
Institución organizadora:
UBA - SFBM SOUTH AMERICAN CHAPTER
Resumen:
Resveratrol rescues
insulin sensitivity in ?obese? adipocytes
Gomez-Mejiba,
SE & Ramirez, DC
Laboratory of Experimental Medicine &
Therapeutics. IMIBIO-SL-CONICET-UNSL. San Luis, San Luis 5700, Argentina. E-mail: ramirezlabimibiosl@ymail.com
Resveratrol is a cell permeable trans-stilbene derivative that can
scavenge intracellularly produced HOCl (J. Biol. Chem, 285:20062/71). Our DIO model in B6 mice showed that epididimal AT
expresses myeloperoxidase (MPO) in AT macrophages (ATM) that also express M1
markers (e.g., IL-6, iNOS). MPO expression was observed in ATM located in the
typical crown-like structures; and also inside adipocytes. Tissue fractionation
showed MPO mRNA in the ATM, but not in adipocyte fraction. Treatment of these isolated
adipocytes with H2O2 blocked glucose uptake. Based on these
findings, we hypothesized that MPO interferes with AT insulin signaling by producing
HOCl and causing oxidation of intracellular components involved in insulin-triggered
signaling. To test this hypothesis we differentiated
human adipocytes and loaded them with human MPO. Treatment of MPO-loaded adipocytes
with H2O2 caused intracellular production of HOCl,
reduced insulin-triggered GLUT-4 translocation to the membrane and glucose
uptake. Furthermore DMPO-based immuno-spin trapping and MS-tandem showed radicalization
of specific components of the insulin signaling (e.g., IRS-1/2, SOCS3, GLUT-4).
These effects were prevented by resveratrol, but not by taurine or methionine
because these cannot pass across the membrane. Together our findings suggest
that resveratrol can protect insulin sensitivity in the obese AT by scavenging
intracellularly produced HOCl.
Preference:
PRESENTACION ORAL